Support Notes for Red Hat Enterprise Linux AS v.4.6 for HP Integrity Servers

nPartitions, halting the operating system from an nPartition with softpowerdown enabled
causes only the resources on the local nPartition to be powered off. You can run the
acpiconfig command with no arguments to check the current setting and the
softpowerdown setting; however, softpowerdown information is displayed only when
different from normal behavior.
To power on hardware that has been powered off, use the PE command at the management
processor command menu. To make an inactive nPartition active, use the management
processor BO command to boot the nPartition past the boot-is-blocked state.
15. This note pertains to Linux running on the following systems: rx8620 and Superdome sx1000
and sx2000. On the rx8620 and Superdome sx1000, the maximum number of I/O chassis that
can be supported per hard partition (also called nPartition) is two. On Superdome sx2000,
the maximum number of I/O chassis that can be supported per hard partition is eight.
16. In a text-based installation, the partition displays from either autopartition or disk druid
will display filesystems of 1 terabyte or greater without a size suffix such as M or G. These
filesystems will appear to be much smaller than they really are.
17. Red Hat Enterprise Linux can be preloaded on the HP Integrity server disk in the factory
prior to customer shipment. In the event of a system disk failure, the recovery process of
this "factory preloaded OS image" is a "cold install" directly from the Red Hat media kit or
the Red Hat Network. For additional instructions on installing Red Hat Enterprise Linux
on an Integrity server, consult the HP integrity Essentials Foundation Pack for Linux User's
Guide.
18. Output from the Management Processor (MP) serial ports may hang due to a failure to
reassert a transmit empty interrupt in the MP UART. When used as a serial console, this
output hang may lead to a hang during Linux boot. This condition may occur on any low-end
Integrity system using the MP console port as the Linux system console. This problem does
not exist on mid-range and high-end Integrity platforms.
When rebooting the system, the user should either manually confirm the system has booted,
or use scripts to track the system boot on the serial console and automatically intervene as
necessary. The only intervention required to continue the boot process is to send a character
to produce a receiver interrupt on the console UART (for example, pressing a key). Note
that while experiencing this console hang is rare, it can happen multiple times on the same
boot cycle.
19. Installation to a software RAID 6 volume may result in a kernel panic. If this occurs, try
using a different RAID type such as RAID 5.
20. The cdrecord program may hang when burning a CD-RW disk with unsupported media
using certain models of CD/DVD-ROM Combo and DVD+RW drives shipped in rx1600,
rx1620, rx2600, rx2620, and rx4640 servers.
Use only approved HP CD-RW media to prevent burn hangs. Try different brands of media
if HP media is not available.
21. The ELILO bootloader can pass command-line options to the Linux kernel. The max_addr=
and mem= options limit the amount of memory used by the kernel.
Some versions of the kernel handle these arguments incorrectly, resulting in an MCA that
crashes the system during boot. If the system boots successfully, there is no risk of a crash
due to this problem.
Booting with max_addr= or mem= is sometimes useful for debugging problems, but is not
a tested feature. A similar effect can be achieved by deconfiguring (with the EFI dimmconfig
command) or physically removing DIMMs.
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